1.  excrescence(n = noun.shape) bulge, bump, extrusion, gibbosity, gibbousness, hump, jut, prominence, protrusion, protuberance, swelling - something that bulges out or is protuberant or projects from its surroundings; "the gun in his pocket made an obvious bulge"; "the hump of a camel"; "he stood on the rocky prominence"; "the occipital protuberance was well developed"; "the bony excrescence between its horns"
is a kind of projection
has particulars: frontal eminence, occipital protuberance, belly, caput, mogul, nub, nubble, snag, wart
Derived form adjective excrescent₁

2.  excrescence(n = noun.body) - (pathology) an abnormal outgrowth or enlargement of some part of the body;
is a kind of appendage, outgrowth, process, growth
has particulars: vegetation
Derived form adjective excrescent₁

   An excrescent appendage, as, a wart or tumor; anything growing out unnaturally from anything else; a preternatural or morbid development; hence, a troublesome superfluity; an incumbrance; as, an excrescence on the body, or on a plant. Jer. Taylor. [1913 Webster]
"The excrescences of the Spanish monarchy." [1913 Webster]

excrescence, n.
1 an abnormal or morbid outgrowth on the body or a plant.
2 an ugly addition.

Derivative:
excrescent adj. excrescential adj.

Etymology:
L excrescentia (as EX-(1), crescere grow)

N  blemish, disfigurement, deformity, adactylism, flaw, defect, injury, spots on the sun, eyesore, stain, blot, spot, spottiness, speck, speckle, blur, tarnish, smudge, dirt, freckle, mole, macula, patch, blotch, birthmark, blobber lip, blubber lip, blain, maculation, scar, wem, pustule, whelk, excrescence, pimple, pitted, freckled, discolored, imperfect, blobber-lipped, bloodshot, injured.

N  convexity, prominence, projection, swelling, gibbosity, bilge, bulge, protuberance, protrusion, camber, cahot, thank-ye-ma'am, swell, intumescence, tumour, tumor, tubercle, tuberosity, excrescence, hump, hunch, bunch, boss, embossment, hub, hubble, tooth, knob, elbow, process, apophysis, condyle, bulb, node, nodule, nodosity, tongue, dorsum, bump, clump, sugar loaf, bow, mamelon, molar, belly, corporation, pot belly, gut, withers, back, shoulder, lip, flange, pimple, zit, wen, wheel, papula, pustule, pock, proud flesh, growth, sarcoma, caruncle, corn, wart, pappiloma, furuncle, polypus, fungus, fungosity, exostosis, bleb, blister, blain, boil, airbubble, blob, papule, verruca, papilla, nipple, teat, tit, titty, boob, knocker, pap, breast, dug, mammilla, proboscis, nose, neb, beak, snout, nozzle, schnoz, peg, button, stud, ridge, rib, jutty, trunnion, snag, cupola, dome, arch, balcony, eaves, pilaster, relief, relievo, cameo, bassorilievo, mezzorilevo, altorivievo, low relief, bas relief, high relief, hill, cape, promontory, mull, forehead, foreland, point of land, mole, jetty, hummock, ledge, spur, naze, ness, convex, prominent, protuberant, projecting, bossed, embossed, bossy, nodular, bunchy, clavate, clavated, claviform, hummocky, moutonne, mammiliform, papulous, papilose, hemispheric, bulbous, bowed, arched, bold, bellied, tuberous, tuberculous, tumous, cornute, odontoid, lentiform, lenticular, gibbous, club shaped, hubby, hubbly, knobby, papillose, saddle-shaped, selliform, subclavate, torose, ventricose, verrucose, salient, in relief, raised, repousse, bloated, (expanded).